One of the best things about San Francisco is how engaged the neighborhoods are. A new park or a housing development doesn't get rubber-stamped here.

The problem comes when they can't let go.

Take the Beach Chalet soccer fields. Please.

I get that there are concerns about the impact on wildlife if grass is replaced with synthetic turf, which some also worry could ooze toxic substances. But c'mon. This debate has been going in circles for two years. An environmental impact report costing almost $1 million found no significant health risk. And it's not as if the idea is to tear up pristine parkland - those are already soccer fields - the idea is just to put in synthetic turf.

Yet opponents battle on and on.

Matters reached a new low recently when a fake e-mail was sent out, purporting to be from the National Institutes of Health, claiming "parents and athletes are expressing concerns regarding the new synthetic fields." Outrageously, the e-mail also said Viking Soccer and San Francisco Microsoccer, which wholeheartedly back the new fields, were having reservations.

It was such a blatant falsehood that agency spokeswoman Marin Allen issued a formal statement saying it had been "misrepresented" and that "the information in these e-mails do not represent the view of the NIH and the sender is not affiliated with NIH."

Phil Ginsburg, director of the city's Recreation and Park Department, could only sigh.

"A good-faith policy debate is one thing," Ginsburg said. "But to scare the bejesus out of parents and kids is another."

Keeping park concept

The coalition of opponents shrugs off the criticism and moves serenely on. Of course the e-mail was out of line, says George Wooding, who calls himself "a concerned citizen, although I run half the (opposition) groups." In fact, he suggests it was generated by the boosters.

"It would have been a great tactic," he says. "My feeling is that Golden Gate Park will be of more value if kept natural. We don't need a stadium there."

Katherine Howard of San Francisco Ocean Edge, a "save Golden Gate Park" advocacy group, suggests "high-quality grass fields without lighting. Because once you put in these fields and urbanize it, you've lost the concept of the park."

Soccer officials, who have been knocking down these phantom arguments for months, can barely keep from pulling their hair out. Nationally known author Po Bronson, who is president of Viking Soccer, not only played on the fields, he broke his hip on the gopher-hole-pocked turf.

"You hear them say, 'Why not just put a grass field out there?' " said Bronson, who cites the foggy, rainy ocean weather. "Grass pitches are locked behind fences for maintenance and rainouts a minimum of a third of the year, often more."

Minimal health hazards

As for the health hazard, synthetic turf is used at 12 other sites. If that's not enough, read the environmental impact report produced by the Planning Department. But I'd set aside plenty of time because it is huge, covering everything from aesthetics to cultural resources to "inhalation of vapors and particulates." In all cases the health hazards were found to be negligible.

Not that it convinced the opponents.

Things are likely to play out as follows: On May 24, the Rec and Park and Planning commissions will conduct hearings to vote on the impact report. The next day, opponents will probably file an appeal, which could take a month. And then another. That would probably be followed by an attempt to get a restraining order from court.